NAME

git-http-backend - Server side implementation of Git over HTTP

SYNOPSIS

git http-backend

DESCRIPTION

A simple CGI program to serve the contents of a Git repository to Git
clients accessing the repository over http:// and https:// protocols.
The program supports clients fetching using both the smart HTTP protocol
and the backwards-compatible dumb HTTP protocol, as well as clients
pushing using the smart HTTP protocol.

It verifies that the directory has the magic file
"git-daemon-export-ok", and it will refuse to export any Git directory
that hasn’t explicitly been marked for export this way (unless the
GIT_HTTP_EXPORT_ALL environmental variable is set).

By default, only the upload-pack service is enabled, which serves
git fetch-pack and git ls-remote clients, which are invoked from
git fetch, git pull, and git clone. If the client is authenticated,
the receive-pack service is enabled, which serves git send-pack
clients, which is invoked from git push.

SERVICES

These services can be enabled/disabled using the per-repository
configuration file:

http.getanyfile

This serves Git clients older than version 1.6.6 that are unable to use the
upload pack service. When enabled, clients are able to read
any file within the repository, including objects that are
no longer reachable from a branch but are still present.
It is enabled by default, but a repository can disable it
by setting this configuration item to false.

http.uploadpack

This serves git fetch-pack and git ls-remote clients.
It is enabled by default, but a repository can disable it
by setting this configuration item to false.

http.receivepack

This serves git send-pack clients, allowing push. It is
disabled by default for anonymous users, and enabled by
default for users authenticated by the web server. It can be
disabled by setting this item to false, or enabled for all
users, including anonymous users, by setting it to true.

URL TRANSLATION

To determine the location of the repository on disk, git http-backend
concatenates the environment variables PATH_INFO, which is set
automatically by the web server, and GIT_PROJECT_ROOT, which must be set
manually in the web server configuration. If GIT_PROJECT_ROOT is not
set, git http-backend reads PATH_TRANSLATED, which is also set
automatically by the web server.

EXAMPLES

All of the following examples map http://$hostname/git/foo/bar.git
to /var/www/git/foo/bar.git.

Apache 2.x

Ensure mod_cgi, mod_alias, and mod_env are enabled, set
GIT_PROJECT_ROOT (or DocumentRoot) appropriately, and
create a ScriptAlias to the CGI:

To enable anonymous read access but authenticated write access,
require authorization for both the initial ref advertisement (which we
detect as a push via the service parameter in the query string), and the
receive-pack invocation itself:

In this mode, the server will not request authentication until the
client actually starts the object negotiation phase of the push, rather
than during the initial contact. For this reason, you must also enable
the http.receivepack config option in any repositories that should
accept a push. The default behavior, if http.receivepack is not set,
is to reject any pushes by unauthenticated users; the initial request
will therefore report 403 Forbidden to the client, without even giving
an opportunity for authentication.

To require authentication for both reads and writes, use a Location
directive around the repository, or one of its parent directories:

Similar to the above, but Apache can be used to return static
files that are stored on disk. On many systems this may
be more efficient as Apache can ask the kernel to copy the
file contents from the file system directly to the network:

ENVIRONMENT

git http-backend relies upon the CGI environment variables set
by the invoking web server, including:

PATH_INFO (if GIT_PROJECT_ROOT is set, otherwise PATH_TRANSLATED)

REMOTE_USER

REMOTE_ADDR

CONTENT_TYPE

QUERY_STRING

REQUEST_METHOD

The GIT_HTTP_EXPORT_ALL environmental variable may be passed to
git-http-backend to bypass the check for the "git-daemon-export-ok"
file in each repository before allowing export of that repository.

The GIT_HTTP_MAX_REQUEST_BUFFER environment variable (or the
http.maxRequestBuffer config variable) may be set to change the
largest ref negotiation request that git will handle during a fetch; any
fetch requiring a larger buffer will not succeed. This value should not
normally need to be changed, but may be helpful if you are fetching from
a repository with an extremely large number of refs. The value can be
specified with a unit (e.g., 100M for 100 megabytes). The default is
10 megabytes.

The backend process sets GIT_COMMITTER_NAME to $REMOTE_USER and
GIT_COMMITTER_EMAIL to ${REMOTE_USER}@http.${REMOTE_ADDR},
ensuring that any reflogs created by git-receive-pack contain some
identifying information of the remote user who performed the push.

All CGI environment variables are available to each of the hooks
invoked by the git-receive-pack.